Starting mechanism for internal combustion engines



Oct. 25, 1966 BAKER ETAL STARTING MECHANISM FOR INTERNAL COMBUSTION ENGINES 2 Sheets-Sheet 1 Filed Aug. 4. 1964 Oct. 25, 1966 A. D. BAKER ETA!- 3,280,811

STARTING MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed Aug. 4. 1964 2 Sheets-Sheet a United States Patent 3,280,811 STARTING MECHANISM FOR INTERNAL COMBUSTION ENGINES Alfred Dickens Baker, Solihull, and John Stanley Clarke, Edgbaston, Birmingham, England, assignors to Joseph Lucas (Industries) Limited, Birmingham, England Filed Aug. 4, 1964, Ser. No. 387,389 4 Claims. (Cl. 123-179) This invention relates to starting mechanism for internal combustion engines, and of the kind comprising an electric motor, a shaft rota-table by the motor, a pinion on the shaft, and a solenoid for moving the pinion axially along the shaft into engagement with a toothed wheel of the engine.

The object of this invention is to provide such a mechanism in a convenient form.

According to the invention a starting mechanism of the kind specified comprises a pair of relatively spring-loaded levers arranged to bear on opposite sides of an abutment movable axially with the pinion, one of said levers being connected to a spring loaded armature of a solenoid Which is movable in a direction at right angles to the axis of the shaft and the arrangement being such that energis-ation of the solenoid Will cause the other lever to bear on the abutment in a direction to move the pinion into engagement with the toothed wheel of the engine and in the event of end-to-end engagement of the teeth the armature can move to its full extent under energisation against the action of the spring action between the levers, whilst on de-energisation of the solenoid the armature spring will cause said one lever to bear on the abutment in a direction to effect disengagement of the pinion from the toothed wheel.

In the accompanying drawings,

FIGURE 1 is a sectional side view of one example of a starting mechanism in accordance with the invention and FIGURE 2 is a section of the mechanism shown in FIGURE 1.

Referring to the drawings there is provided an electric motor 1 having a rotor shaft 2 which at one end extends from the motor and is supported at its free end in a bearing 3 in a cover 4. Surrounding the extension of the shaft is a sleeve 5 which has quick-pitch screw thread connection with the shaft. Moreover, the end of the sleeve remote from the motor is enlarged to form the outer part of uni-directional clutch 6 of the roller type. The inner part of the clutch is formed on, or secured to a pinion 7 also surrounding the shaft and movable axially thereon with the sleeve.

Located between an annular peripheral shoulder on the sleeve, and a split ring engaging a groove therein, is an abutment in the form of an annular thrust washer 8 against opposite faces of which a pair of relatively spring-loaded levers 9a, 9b are arranged to bear. The pair of levers are pivotally mounted within the cover about a common axis constituted by a pin 10 and are relatively spring-loaded by means of a coiled torsion spring 11. The lever 9a is of bell-crank form having its one arm divided to provide two limbs 12 arranged to bear on the side of the abut-ment remote from the motor at diametrically opposite points. The other arm of this lever is connected by a link 13 to a spring-loaded armature 14 of a solenoid mounted on the cover with its axis at right angles to the shaft. The lever 9b is of U-shape and has its limbs 15 disposed to bear on the side of the abutment adjacent the motor at diametrically opposite positions. Moreover, by abutment of a stirrup 15a, on the lever 9b, with part of the lever 9a the movement of the pair of levers by the torsion spring is limited so that "ice when the forked lever contacts the abutment, the U- shaped lever will be just clear of the abutment, and vice versa.

On the solenoid armature 14 is the movable contact 16 of a motor controlling switch which is closed when the armature has been fully drawn in as a result of energisation of the solenoid coil. Moreover, the commutator (not shown) and associated brushes of the motor (not shown) are conveniently situated at the end of the rotor remote from the shaft extension.

When in use, a remotely disposed switch is closed to complete a circuit through the solenoid, the armature 14 will be drawn into the coil in a direction away from the shaft. As a result the limbs 15 of the U-shaped lever 9b will bear on the abutment 8 and thereby move the sleeve 5, together with the pinion 7, axially along the shaft to engage the pinion with the toothed engine flywheel 17. During this axial movement a small angular movement will be imparted to the pinion due to the quick pitch screw-thread or equivalent connection between the sleeve and shaft. When the solenoid has been fully drawn into the coil the switch is closed and the motor is energised to start the engine.

In the event of the pinion engaging the flywheel with their respective teeth end-to-end, the armature can still move fully into the coil against the additional action of the torsion spring 11 acting between the levers. Thus the motor will be started and engagement of the pinion can be effected by the torsion spring as the pinion rotates.

After the engine has started the uni-directional clutch 6 prevents the engine driving the motor. Moreover, as soon as the remoteswitoh is opened the armature spring will cause the forked lever 9a to bear on the abutment 8 in a direction to disengage the pinion. Also, the limited angular movement between the levers 9a, 9b is such that before the forked lever bears on the abutment the solenoid armature will have moved sufficiently to break the motor circuit.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

1. An engine starting mechanism comprising in combination a housing, a rotor mounted for rotation Within the housing, said rotor having an extended rotor shaft, a pinion mounted on said shaft and driveable thereby, said pinion being movable axially upon said shaft, an abutment plate disposed about said shaft and connected to said pinion, said abutment plate being disposed intermediate the pinion and the rotor and defining a pair of abutment surfaces on opposite sides thereof, a pivot mounted within the casing, a pair of levers mounted upon said pivot and having free ends disposed to bear upon the abutment surfaces respectively, a solenoid mounted upon the casing, an armature movable by said solenoid, resilient means acting to move the armature in opposition to the solenoid, link means operatively connecting the armature to the lever which is disposed to contact the abutment surface of the abutment plate which is presented to the pinion, further resilient means acting intermediate the two levers for biasing the free ends thereof towards each other and stop means acting between the two levers so as to ensure that the free ends thereof cannot contact the abutment surfaces at the same time.

2. An engine starting mechanism comprising in combination, a housing, a rotor mounted for rotation within the housing, said rotor having an extended rotor shaft, a pinion mounted on and slidable axially on said shaft, a collar mounted on said shaft and driveable thereby, said collar being axially moveable upon the shaft, an abutment plate mounted upon said collar, said abutment plate defining a pair of abutment surfaces on opposite sides thereof, a one way clutch through which the collar is connected to said pinion, a pivot mounted within the easing, a pair of levers mounted upon said pivot and having free ends disposed to bear upon the abutment surfaces respectively, a solenoid mounted upon the casing, an armature movable by said solenoid, resilient means acting to move the armature in opposition to the solenoid, link means operatively connecting the armature to the lever which is disposed to contact the abutment surface of the abutment plate which is presented to the pinion, further resilient means acting intermediate the two levers for biasing the free ends towards each other and stop means acting between the two levers so as to ensure that the free ends thereof cannot contact the abutment surfaces at the same time.

3. An engine star-ting mechanism comprising in combination, a housing, a rotor mounted for rotation within the housing, said rotor having an extended rotor shaft, a pinion mounted on and slidable axially on said shaft, a collar mounted on said shaft and driveable thereby, said collar being axially moveable upon the shaft, an abutment plate mounted upon said collar, said abutment plate defining a pair of abutment surfaces on opposite sides thereof, a one way clutch through which the collar is connected to said pinion, a pivot mounted within the casing, a pair of levers mounted upon said pivot and having free ends disposed to bear upon the abutment surfaces respectively, a solenoid mounted upon the. easing, an armature moveable by said solenoid, resilient means acting to move the armature in opposition to the solenoid, link means operatively connecting the arm; ture to'the lever Which is disposed to contact the abu rnent surface of the abutment plate which is presente to the pinion, further resilient means acting intermediat the two levers for biasing the free ends towards eac other, stop means acting between the two levers so 2 to ensure that the free ends thereof cannot contact th abutment surfaces at the same time, and a motor cor trolling switch actuable by movement of said armaturi said switch being arranged to be closed when the arm: ture is moved against the action of the resilient mear by the solenoid.

4. A mechanism as claimed in claim 3 in which tk abutment plate is of annular form and each lever-is pr( vided with two arms which contact the respective abu ment surface of the plate at diametrically opposite point References Cited by the Examiner UNITED STATES PATENTS 1,942,573 1/1934 Sekella 74 1,974,985 9/1934 Cunnius 74- 3,l77,728 4/1965 Farison '74- FOREIGN PATENTS 923,883 2/1955 Germany.

755,594 8/1956 Great Britain.

964,675 7/1964 Great Britain.

MARK NEWMAN, Primary Examiner.

0 LAWRENCE M. GOODRIDGE, Examiner. 

1. AN ENGINE STARTING MECHANISM COMPRISING IN COMBINATION A HOUSING, A ROTOR MOUNTED FOR ROTATION WITHIN THE HOUSING, SAID ROTOR HAVING AN EXTENDED ROTOR SHAFT, A PINION MOUNTED ON SAID SHAFT AND DRIVABLE THEREBY, SAID PINION BEING MOVABLE AXIALLY UPON SAID SHAFT, AN ABUTMENT PLATE DISPOSED ABOUT SAID SHAFT AND CONNECTED TO SAID PINION, SAID ABUTMENT PLATE BEING DISPOSED INTERMEDIATE THE PINION AND THE ROTOR AND DEFINING A PAIR OF ABUTMENT SURFACES ON OPPOSITE SIDES THEREOF, A PIVOT MOUNTED WITHIN THE CASING, A PAIR OF LEVERS MOUNTED UPON SAID PIVOT AND HAVING FREE ENDS DISPOSED TO BEAR UPON THE ABUTMENT SURFACES RESPECTIVELY, A SOLENOID MOUNTED UPON THE CASING, AN ARMATURE MOVABLE BY SAID SOLENOID, RESILIENT MEANS ACTING TO MOVE THE ARMATURE IN OPPOSITION TO THE SOLENOID, LINK MEANS OPERATIVELY CONNECTING THE ARMATURE TO THE LEVER WHICH IS DISPOSED TO CONTACT THE ABUTMENT SURFACE OF THE ABUTMENT PLATE WHICH IS PRESENTED TO THE PINION, FURTHER RESILIENT MEANS ACTING INTERMEDIATE THE TWO LEVERS FOR BIASING THE FREE ENDS THEREOF TOWARDS EACH OTHER AND STOP MEANS ACTING BETWEEN THE TWO LEVERS SO AS TO ENSURE THAT THE FREE ENDS THEREOF CANNOT CONTACT THE ABUTMENT SURFACES AT THE SAME TIME. 